BREATH SELECTION FOR ANALYSIS
Methods and systems are described to obtain and analyze a gas sample from a desired section of the breath of a person, while accounting for erratic, episodic or otherwise challenging breathing patterns that may otherwise make the capturing of a gas sample from the desired section of breath difficult. These techniques may provide more reliable, accurate and adequate samples of gas such as end-tidal gas, and ultimately an accurate analysis of the sample captured.
1 - 18 . (canceled)
19 . An apparatus for breath selection comprising:
a sensor that measures a plurality of breathing parameters of a series of exhaled breaths, wherein a plurality of predetermined criteria are based on the plurality of breathing parameters;
a processor that applies a breath selection algorithm to the series of exhaled breaths and identifies a first valid exhaled breath when the first exhaled breath meets at least two or more of the plurality of predetermined criteria, the at least two or more predetermined criteria comprising a peak amplitude and a time-based value, and wherein the breath selection algorithm further identifies a second valid exhaled breath when the second valid exhaled breath meets a percent comparison of the two or more predetermined criteria;
a breath sampling system that captures the second valid exhaled breath; and
a gas analyzer that measures an analyte in the second valid exhaled breath.
20 . The apparatus of claim 19 , wherein the analyte comprises carbon monoxide.
21 . The apparatus of claim 19 , wherein the time-based value is selected from the group consisting of a time duration below the peak amplitude value, a time duration below a baseline value, an inspiratory time, a breath period time, an expiratory time, and end-tidal time, a CO 2 value over time, and an O 2 value over time.
22 . The apparatus of claim 19 , wherein the breath selection algorithm further comprises identifying a second valid exhaled breath based on a breath period between the first and second valid exhaled breaths.
23 . The apparatus of claim 22 , wherein the breath period is based on a breath rate.
24 . The apparatus of claim 19 , wherein the sensor comprises a carbon monoxide sensor, a pressure sensor, or an infrared (IR) sensor.
25 . A method for selecting a valid exhaled breath for analysis comprising:
identifying a first valid exhaled breath based on the first valid exhaled breath meeting at least two or more predetermined criteria, the at least two or more predetermined criteria comprising a peak amplitude and a time-based value;
identifying a second valid exhaled breath based on a percent comparison of the at least two or more predetermined criteria;
capturing the second valid exhaled breath using a breath sampling system; and
measuring an analyte in the second valid exhaled breath.
26 . The method of claim 25 , wherein the analyte comprises carbon monoxide.
27 . The method of claim 25 , wherein the time-based value is selected from the group consisting of a time duration below the peak amplitude value, a time duration below a baseline value, an inspiratory time, a breath period time, an expiratory time, and end-tidal time, a CO 2 value over time, and an O 2 value over time.
28 . The method of claim 25 , wherein identifying the second valid exhaled breath is further based on a breath period between the first and second valid exhaled breaths.
29 . The method of claim 28 , wherein the breath period is based on a breath rate.
30 . An apparatus for breath selection comprising:
a sensor that measures parameters of a first exhaled breath, a second exhaled breath, and a third exhaled breath;
a first processor that determines if a first measurement of the first exhaled breath meets a first predetermined criteria;
a second processor that determines if a second measurement of the second exhaled breath meets a second predetermined criteria, wherein the second measurement is made when the first measurement is determined to meet the first predetermined criteria;
a third processor that determines if a third measurement of the third exhaled breath meets a third predetermined criteria, wherein the third measurement is made when the second measurement is determined to meet the second predetermined criteria; and
a breath sampling system that stores the third exhaled breath when the third processor determines the third measured parameter meets the third predetermined criteria.
31 . The apparatus of claim 30 , wherein the third predetermined criteria is based upon a trend associated with a plurality of breaths.